(ref.doc)Semantics

Semantics:

p 85
Lullaby: Little-Used Lilliputian Language Appropriate for Beginners
and the Young

p 87
Five fundamental approaches:
- attribute grammars, which extends the grammar by a set of rules for
  computing properties of language constructs.
- translational semantics, where the semantics is expressed by a
  translation scheme to a simpler language.
- operational semantics, which specifies the semantics by providing an
  abstract interpretor.
- denotational semantics, which associates with every programming
  construct a set of mathematical functions defining its meaning
- axiomatic semantics, which for every programming language defines a
  mathematical theory for proving properties of programs written in
  this language.

p 88, Attribute (affix) grammars
The process of adding semantics to a syntactic description, abstract
or concrete, is often called *decoration*.

- To decorate a construct, you define *attributes* which describe the
  semantic properties of specimens of this construct.
- To decorate a production, you define one or more *rules* expressing
  the relationships between the attributes of the specimens of its
  left-hand side construct and the attributes of the right-hand side's
  construct specimens.

p 96
Oulala: Outrageously Useless Lilliputian Assembly Language for
Analphabets

p 104
Operational semantics may be viewed as the application to language
design and implementation of ideas that have attracted much attention
in software engineering: the notions of *rapid prototyping* and
*executable specification*.

p 111, 4.6 Axiomatic semantics
The meaning of a pre-post formula {P} a {Q} is the following:
If *a* is executed in a state in which assertion *P* is satisfied,
then it will result in a state in which assertion *Q* is satisfied.